Name______________________________________
Mendel’s Peas
Go to: http://www2.edc.org/weblabs/Mendel/MendelMenu.html
Click Enter Web Lab
CAUTION: Don’t hit the back button or you will have to restart the activity.
Directions: After clicking “Enter the Web Lab” you will see a screen with an introduction to Gregor
Mendel. Read the short paragraph, answer the first question below, and then click next. After that, read
the next short sentence and answer question number two below, and then click next.
Introduction
1. Gregor Mendel lived in the 1800s long before anyone knew _________________________.
2. List 3 reasons he used pea plants:
Plant and Cross
Next click “plant” and observe the five different pea plants, and answer the following question.
3. List the traits that you can see in the 5 plants that Mendel planted for you. Roll your cursor over each plant to
see the peas close up, click “next” when you are finished. In the space provided below, answer Mendel’s
question on how many traits you found, and then click “done” to see if you were right. Then click “next” and
go to question four.
4. Making crosses: To make a cross you will choose any two plants and place them in the boxes. Then you will
choose one trait at a time for example pea color, you would write pea color in the trait box, and in the Parent 1
Phenotype box you would write the color of the pea of the first plant chosen in your box. For Parent 2 Phenotype
you would write the color of the pea in the second plant you chose. For F1 Phenotype you would fill in how many
yellow peas you got from your cross and how many green peas. Make four of these crosses. When finished click
“next”.
Trait
Parent 1 Phenotype
Parent 2 Phenotype
F1 Phenotype
Pea Color
Yellow
Yellow
4 Yellow, 1 green
Note: The pea plants are randomly generated, so they may change when you do the next cross.
Predict Results- follow the instructions on the screen, and answer questions five and six.
5. When you cross the plant with itself, what pea shape do the offspring have? ___________________.
6. When you cross two plants with wrinkled peas, what shape will the peas have? ________________.
Pedigree- Now you will be using boxes to represent the plants. You can roll over the boxes to see the plants.
7. Click on two plants to cross them and show the results of your cross. Under F1 Phenotype, record the number
out of 10 for each phenotype. For example, 4/10 white flower and 6/10 purple flower.
Trait
Parent 1 Phenotype
Parent 2 Phenotype
F1 Phenotype
8. Which color was dominant? __________________________.
9. Select at least 3 traits and complete crosses to see which allele is dominant. Record your results.
Under F1 Phenotype, record the number out of 10 for each phenotype. For example, 4/10 white flower and 6/10
purple flower.
Trait
Parent 1 Phenotype
Parent 2 Phenotype
F1 Phenotype
Pea Shape
Wrinkled
Wrinkled
10/10 Wrinkled
10. When you get the correct results for all of them, write down which allele is dominant.
Trait
Pea Shape
Dominant
Round
Punnett Squares
Go to http://www2.edc.org/weblabs/Punnett/PunnetSqMenu.html
Click Enter Web Lab
Complete the activity. When you get to the end, remember that you’re trying to produce albino long tailed
lemmings. What is the genotype that you’re trying to produce (be careful here, you’re looking for 2 traits!!)
Genotype __________________________
Look for that genotype in the punnett squares that they show you. Which guinea pigs did you have to mate?